3 May 2012

The Unconscious and the Psychophysicians

In discussion of the preceding post about Freud and the unconscious, Michael of Ombhurbhuva noted that Henri Bergson had, in one of his books, responded to Fechner’s ideas about consciousness and the unconscious. I had begun writing a comment about Fechner, but then it got to be such a long ramble I decided it might work better as a post. So I moved the comment to my clipboard where I intended to finish it off and post it this morning. Sadly my computer shut down unexpectedly, which meant the erasure of this comment-cum-post. Pissed off, I intended just to forget it, but through obsession or obduracy I found myself on my morning walk mourning and rehearsing what had been lost. So now here I am, rewriting the post. I don’t doubt that it will be different from, and inferior to, the legendary lost text.

As I recall, the central ideas were three:

The experimental psychologists before Freud regarded the unconscious not as a kind of jail where previously-conscious thoughts and imaginings were consigned by the ego for having been judged too naughty, but as the wellspring and foundation of conscious thought.

The early experimentalists, like Freud, regarded inhibition of thought as an artificial obstacle to freedom rather than as an integral mental function. As for Freud, this theory was grounded in metaphysics rather than science, and arguably it inhibited for a time the understanding of mental processes even as it stimulated experimental investigation.

The early experimentalists regarded the unconscious mind as composed of elementary percepts and ideas. In this regard too their philosophical precommitments both advanced and hindered their empirical work.

Gustav Theodor Fechner merits a chapter in Edmund Boring’s 1950 landmark A History of Experimental Psychology as the first psychologist who actually performed rigorous scientific experiments — a research program Fechner called “psychophysics.” Fechner, whose first important work was published in 1851, assayed to demonstrate with empirical precision a theory propounded thirty years earlier by the philosopher Johann Friedrich Herbart. In Herbart’s scheme, human psychology is both mechanical and elemental. Though the mind is a unified whole, its content is composed of a storehouse of distinct percepts and ideas. These mental elements jostle with each other and reinforce one another in an ongoing effort to attain conscious expression. In 1825 Herbart wrote:

“Every movement of the ideas is confined between two fixed points: their state of complete inhibition, their state of complete liberty… There is a natural and constant effort of all the ideas to revert to their state of complete liberty (absence of inhibition).”

Herbart worked out his ideas in the form of mathematical equations; however, his formulae for mental dynamics were based on logic and theory rather than empirical evidence. Fechner began the work of refining the elegant abstractions with messy data and statistical analysis. His work focused largely on visual perception. Since it was impossible for Fechner to tamper directly with the retina and optic nerve and visual cortex, he systematically varied the environmental stimuli to which the human neural pathways respond. In particular, he wanted to find the “just noticeable difference,” or “jnd”: the precise intensity of a stimulus that triggers the buildup of neural activation to the point where it passes the limen into consciousness. Fechner believed that, whereas stimulus information is continuous, sensations are discrete: a specific pitch or volume of sound, a distinct color or intensity of luminance. If the stimulus activates the neural sensation to a sufficient level (the jnd), that sensation passes the limen into conscious perception.

If, per Herbart, all elements of the mind tend toward uninhibited expression, why don’t all of the elementary percepts — specific colors, brightnesses, pitches, etc. — clamor to become conscious at the same time? Because, Fechner reminds us, the elementary mental content must be activated by environmental stimuli. Still, Fechner labels those sensations that don’t reach the jnd for becoming conscious as “negative sensations.” By implication, sounds and sights in the environment don’t just trigger the corresponding sensations in the mind; they also inhibit all of the other competing sensations. In this sense the environment simultaneously triggers the free expression of some elements of mental content while imposing external restraints on other elements.

Now back to the presuppositions. Why had Herbart insisted that mental content consisted of pre-existing percepts and ideas? Arguably the historical fact that in 1804 Herbart succeeded Kant as chair at Konigsberg is important. Why for Herbart were the elements of mind separate and distinct? Because Herbart saw himself as a disciple of Leibnitz, philosophical father of the “monad.” Why had Herbart been so insistent that free expression of mental content was its natural tendency, with inhibition imposing an artificial constraint? As a philosopher, Herbart contended that only positive things and forces are real. Constraint, being a negative force, is unreal and a hindrance to reality.

As Herbart’s intellectual heir, Fechner perpetuated these presuppositions. Why then did he focus not on the contents of the mind but on the stimulus value of the environment? Before he turned to psychology, Fechner had been a physicist. In 1839 he suffered what today we might call a nervous breakdown or burnout: William James described it as “habit neurosis;” Fechner regarded it as a spiritual crisis. It took him three years to recover, during which time he became deeply religious. He embraced panpsychism, writing a treatise describing the mental life of plants. Writes Boring:

“His philosophical solution of the spiritual problem lay in his affirmation of the identity of mind and matter and in the assurance that the entire universe can be regarded as readily from the point of view of its consciousness… The demonstration of the consciousness of plants was but a step in the program.”

By implication, the resonance of sensation with environmental stimuli beyond the jnd could be construed as the material world becoming conscious of itself.

I recall that in the earlier, now vanished version of this post I noted similarities and differences of the psychophysicians’ understanding of mind compared with contemporary neuroscientific models. Certainly it’s possible to trace the lineage through the intervening two hundred years from Herbart to the present. Perhaps the most important difference is that the neurons aren’t assigned to discrete percepts or ideas that either do or do not pass the limen into consciousness. Rather, even what in our conscious awareness we regard as elements are distributed more widely across multiple neurons and synaptic connections. Bringing an idea into consciousness doesn’t consist of retrieving it as a discrete unit, but of assembling it dynamically from this wider neural activity. One consequence is that the current version of this post probably contains not a single 4-word string that is identical with its lost predecessor. My retrieval from memory is also a rethinking.

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That genealogy is very interesting. A certain orientation can be given to a subject which remains as a vestige. The only half remembered factoid that I had in my brain was the cure for Fechner’s depression. A woman friend told him that she had a dream in which it was revealed that a feed of ham cooked in Rhine wine would lift it. And it did…for a while.

Yes that is interesting. Here’s what Boring has to say about Fechner’s views on the mind-body relation:

Fechner’s psychophysics has played an important part in the history of psychophysical parallelism for the reason that mind and body, sensation and stimulus, have to be regarded as separate entities in order that each can be measured and the relation between the two determined. Fechner’s psychology therefore, like so much of the psychology that came after him, seems at first to be dualistic. It is true that he began with a dualism, but we must remember that he thought he had shown that the dualism is not real and is made to disappear by the writing of the true equation between the terms.

But now I must describe my variant on the dreamcure for Fechner’s depression. I did have some leftover pork roast, which I had previously grilled over charcoal and mesquite. To go with it tonight I sauteed in olive oil some minced eggplant, green bell pepper, onion, and garlic, then added to it some black beans, chicken broth, and green enchilada sauce. While this sauce was reducing I prepared some grits with just a bit of cream added. Then I prepared also some green beans with onion, mushroom and sour cream. So on the plate we had the pork, thinly sliced, and a dollop of the grits with the egglplant-black bean concoction poured over both, green beans on the side. Serve with chilled chardonnay and voila: the cure! It really was delicious; the vegetarian version would have been almost as good.

‘It really was delicious; the vegetarian version would have been almost as good.”

Doubt it. I too believe in the curative powers of delicious foods, although I make sure not to overindulge as I was doing last year. But the Mesquite Grilled Pork sounds so good, makes me think of that lusty end to Zarathustra, when he wants roast lamb with sage–“I love it like that”.

Don’t really believe it was the ‘feed of ham in Rhine wine’ in particular, but mainly that she dreamed about more or less any food that would cure the depression. Probably was referring to fresh hams, not cured ones, and does sound good. But he must have believed that it had to be that literally.

I DO find that, by now, I’ve become such an experienced cook that any slight failure can, in fact, make me somewhat depressed! It’s asparagus season, and that must be absolutely perfect; I think asparagus is my favourite food. You know what? Vegetarians usually don’t like it much. Typical. I never knew of one that served it. Much prefer kale and bitter greens. Also using tons of eggplant myself right now, and really hitting the parmesan regularly now. Kasseri or Osiago cheese make a divine Chicken Pasta with some Prosciutto, fresh tomatoes and some jalapenos, a few other things. I’ll do that Monday. At last minute, put entire enormous bunch of fresh basil, with the heat turned off so that it just wilts.

We didn’t grow any basil this year, unfortunately. Most Americans seem to be repulsed by lamb, and also veal — the young animals. I love lamb: roasted, sauteed, curried, kebabed, couscous… In Italy practically every meat dish features veal; at restaurants here even the parmigiana and the marsala are made with chicken. I don’t know Kasseri, but the pasta dish sounds very fine.

Fechner, after leaving physics and founding experimental psychology, went on to yet another career as the founder of experimental aesthetics. He focused mainly on painting and the ability to distinguish between authentic Holbein Madonnas, say, and forgeries. I suspect that there are culinary schools in which the psychophysics of taste perception form part of the technique, tweaking ingredients to find the just noticeable differences in flavors. Probably also the corporate vintners do systematic variations in blends, aging, oaking and so on to achieve optimal citrus and floral and cherry notes.

Discovered Kasseri by accident, thought I was getting some Romano or Parmesan, in same case. It’s a Greek semi-soft cheese, and Osiago is almost identical. But you could use Fontina to just as good effect, and that’s everywhere and delicious. It’s quite an inspired pasta, related to good Carbonaras, with the addition of the chicken and tomatoes. I’m sure you could use bacon as well, but Prosciutto is always special if expensive, so I get it rarely.

I’ve started reading Bergson’s Matter and Memory. The most attractive feature of his theorizing so far is his emphasis on the world as the originating source of perception, with the brain’s representation of the world being secondary. There is no need to project the assembled brain-image out into the world, because the world already presents itself out there. Experimentalists and cognitivists lost sight of that important insight with their emphasis on neural pathways, computational models, information processing systems and so on. In this regard Bergson resonates more with JJ Gibson’s theories of direct perception, aka ecological perception. Bergson also contends that visual perception is useful particularly for the perceiver’s taking intentional action in the world rather than for discovering truth. That too is good ecological thinking: visual perception is instrumental, not abstract. I’ll hold those good thoughts in mind as I proceed.

But here’s a bit from Bergson that I just read regarding the unconscious. He’s discussing people who, through some failure in the visual-neural system, are blind. “Visual perception,” Bergson asserts, “has therefore become impotent, and this very impotence is unconsciousness.” First, evidently he regards all visual perception as conscious, which presupposes a notion of perception that’s at variance with what his contemporaries thought, and with what is thought today. Second, he seems to regard unconsciousness as a total lack of responsiveness to the external stimulus. I.e., he doesn’t acknowledge a continuum between total visual obliviousness to the environment and concentrated perceptual attention focused on some specific object or feature of the environment. This must be related somehow to Bergson’s seemingly odd contention that everything in the world is an image, with visual perception being the conscious diminished reflection of those world-images in which the perceiver is immersed.